"cold-contact" seems to be used as a verb and a noun.
What does it mean if I cold contact someone?
Does that mean I am contacting someone I don't know?
I think it may mean that the contact was not initiated by the person you are contacting. He is not expecting this contact, and presumably does not especially desire it (or he would have asked to be contacted.)
Cold calling and cold contacts are ways (proverbially difficult) to drum up business by coaxing the uninterested to buy your product or service.
You call (or call on) people who don't particularly want to hear from you, and try to sell them something.
On the other hand, contacts with those who have expressed an interest in the product or service are often called "leads."